Details

Italian beauty meets electronic precision in Campagnolo's brilliant Record EPS Rear Derailleur. Campagnolo uses an advanced parallelogram design for impeccable, lightning-fast shifting of up to all 11 gears with a single button push. Stop on any gear in between and the position sensor makes micro-adjustments to ensure perfect alignment every time. The construction pairs carbon and cold-forged aluminum to create an ultra strong and extremely light derailleur. Plus, the pulleys roll on super-efficient ceramic bearings and are made from a special rubber that renders the drivetrain virtually silent.

An important part of a rear derailleur's job is keeping the chain taut as you change gears. Chain-wrap capacity is a number that tells whether or not a derailleur will be able to do this on the drivetrain you plan to use it on. Calculate chain-wrap capacity with this formula: Chain-wrap capacity = (large chainring - small chainring) + (large rear cog - small rear cog). Example: 53/39 chainrings and a 12-23 cassette: (53 - 39 = 14) + (23 - 12 = 11) = 25-tooth chain-wrap capacity.